Ultimate dispersion of metallic and ionic platinum on ceria. Issue 21 (1st April 2019)

• Record Type: Journal Article
• Authors: Tovt, Andrii; Bagolini, Luigi; Dvořák, Filip; Tran, Nguyen-Dung; Vorokhta, Mykhailo; Beranová, Klára; Johánek, Viktor; Farnesi Camellone, Matteo; Skála, Tomáš; Matolínová, Iva; Mysliveček, Josef; Fabris, Stefano; Matolín, Vladimír
• Is Part Of: Journal of materials chemistry. Volume 7:Issue 21(2019)
• Page Start: 13019
• Page End: 13028
• Publication Date: 2019-04-01
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c9ta00823c
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Smallest metallic (blue) and ionic (grey) Pt objects on ceria are shaped and controlled by surface oxygen content. Abstract : Ceria represents a technologically indispensable reducible catalyst support. Besides the general impact on the surface chemistry, the oxygen content of the ceria surface directly influences the dispersion of ceria-supported metal nanoparticles, and the properties of ceria-supported metal catalysts. We investigate the role of oxygen atoms on a CeO2 (111) surface in supporting Pt as smallest metallic Pt clusters or, concurrently, as monodispersed Pt 2+ ions. We demonstrate that the necessary condition for the formation of Pt 2+ ions is the availability of lattice O or excess O atoms at surface step edges. Although Pt 2+ ions can exist on partially reduced surfaces, excess O atoms are required to maximize the capacity of the surface to accommodate Pt 2+ and to trigger the redispersion of metallic Pt clusters. Our study provides atomic-level understanding and control of the highest dispersions of Pt on the ceria surface for advancing the state-of-the-art Pt/ceria catalysts that are presently identified at the verge of single-atom Pt dispersion.